MFI2665XEM8 Fridge not cooling properly

[barkster]

First off I've gone through the flow chart.  I have the fridge set to 33 but sometimes I open it and it is 45-50, I took apart freezer bottom, the evaporator fan is running and everything in freezer is frozen. Next I took out the icemaker and pulled out the fan and the damper and plugged everything in and sat it on shelf and let it run, I watched the damper open up and the fan turn on so that is working.  I can't figure out why it won't get below 40 nor stay near it.  I searched the parts diagram looking for thermostat for fridge but only one I could find was inside the ice maker.  Does that control when to turn on the fridge fan and open damper?  It does not make ice so that's only thing I could think of.  I'm just wondering what controls the fridge temperature control?  I'm thinking it is either something with temperature control or freon since damper and fan seem to be working?  Any ideas?  Thanks

[16345Ed]

I’d suspect this if the evaporator is frosted and fan is running. 

Part number: WPW10196393

[barkster]

I checked and it has a tiny little bit of frost on it, I've watched the damper open and close and when I hear the fan on behind ice maker I can feel it blowing air into fridge.  I almost feel everything is working it just thinks fridge is colder than it is but I can't find a thermostat in the fridge and no one has confirmed how controller knows temp of fridge.

[16345Ed]

FF thermistor is under light cover. 

[barkster]

Thanks, i found it under there and I can't find that on any parts diagrams, does it use the same thermsistor as the freezer?  They look the same.  

[mraswm]

Not 100% sure on this, but I do believe this is the right thermistor kit for you.

https://www.repairclinic.com/PartDetail/Thermistor/W10316760/1876627

[barkster]

Thanks don't look the same but maybe, the one in the fridge has 1249 written on it and the one in the freezer has 1218 written on it.  They definitely aren't the same, I put two of the same ones on them and now the compressor won't come on assuming its because the one in the freezer is wrong.  I'll keep digging for correct ones, I think the two I bought are the correct ones for the fridge section because now my fan behind the ice maker is coming one whereas before it wasn't.  I'll prob just stick the old one back on freezer since I think fridge section is working correctly now. I just don't know why they don't have that on the parts diagram.

[Rhubarb Tau]

21 minutes ago, barkster said:

the one in the fridge has 1249 written on it and the one in the freezer has 1218 written on it.

That's a date code, has nothing to do with the part #. If you suspect a Thermistor (sensor) problem, it's easy to test. Find your printed Tech Sheet (check under the RH Upper Hinge Cover, or behind the Toe-Kick). Measure the resistance of the sensor in question in icewater. It should be close to the spec value.

Every Thermistor on this unit will be the same value, Ref. and Frz. sensors are interchangeable.

[16345Ed]

15 hours ago, Rhubarb Tau said:

Every Thermistor on this unit will be the same value, Ref. and Frz. sensors are interchangeable.

Yep, thermistors are the same. 

You must have forgot to connect something if compressor isn’t running. Double check everything you’ve done. 

[barkster]

all so weird because I put back the original thermsistor in the freezer and compressor came on as normal.  Only thing I've disconnected was thermsistors and they were definitely connected. Oh well thanks for help, I'll look for a tech sheet. 

[16345Ed]

5 hours ago, barkster said:

all so weird because I put back the original thermsistor in the freezer and compressor came on as normal.  Only thing I've disconnected was thermsistors and they were definitely connected. Oh well thanks for help, I'll look for a tech sheet. 

Did you test the “new” thermistor? Maybe it was bad out of the package?